I have an 05 gt with 110k miles, all stock, no mods at all, no custom tune. In traffic today while sitting at a light the 'engine failsafe mode' came on the display and the engine shut off. You can start it, but it will immediately stall. I had to trailor it home. I pulled the following codes out of the computer; p2104,p2106,p2111, & p2135. Not absolutely sure what these codes are, my book lists 104,106,111, & 135 but I can't find what the '2' after the 'p' means. I washed the car about 2 hours earlier including flushing out under the hood. Nothing else out of the ordinary, no hard driving and the oil and cooling are fine. I hope it is something I can fix, I haaaaate!! the dealer hear and I need this car back on the road, my wife drives it every day to work and we don't have a backup right now.

I have an 05 gt with 110k miles, all stock, no mods at all, no custom tune. In traffic today while sitting at a light the 'engine failsafe mode' came on the display and the engine shut off. You can start it, but it will immediately stall. I had to trailor it home. I pulled the following codes out of the computer; p2104,p2106,p2111, & p2135. Not absolutely sure what these codes are, my book lists 104,106,111, & 135 but I can't find what the '2' after the 'p' means. I washed the car about 2 hours earlier including flushing out under the hood. Nothing else out of the ordinary, no hard driving and the oil and cooling are fine. I hope it is something I can fix, I haaaaate!! the dealer hear and I need this car back on the road, my wife drives it every day to work and we don't have a backup right now.

I washed my engine last week and got a code for lean condition on one side. I cleared it and it never came back. I just chalked it up to me not getting all of the water blown out of the engine bay. Never thought about it again till I read this thread.

The code definitions you listed are wrong. The P means powertrain. A 0 in the second digit would mean it is an SAE generic code, a 1 usually means manufacturer code. Not sure what a 2 means, probably another lefel of manufacturer code, which means it won't be defined in most universal guides. The 3rd digit is the system, and the last two are the fault. I can't access anything to identify those codes right now, if you haven't gotten an answer by the time I go to work monday I'll take a look and see what they point too.

That being said, it is possible you may have gotten too much water on the PCM (front passanger side of engine compartment), look and see if it is wet, and let the car dry out for a while with the hood open to see what happens.

Great responces here, thanks. There was no overheating, I did find a tiny bit of water in the bottom of the air cleaner box. I disconnected everything in the throttle area and cleaned with electrical contact cleaner. I let the car dry for 24 hours now. Just tried it again, same thing; you can start it but it will immediately shut off.

Just got it running but still in failsafe mode. Now it won't let me go over 4000 RPM. I took the connections off the throttle sensor, throttle actuator, and PCM and cleaned them with electric contact cleaner. I reconnected the PCM while the key was in the on position. I reconnected the other two and tried starting it. This time it started and was working fine. I let it sit and idle for a few minutes then started rev'ing it. I then let it idle a few minutes longer and then shut it off and restarted it. It worked normal for a few more minutes and then after rev'ing again went into this current state. All gages reading good and at least my wife will be able to get to work tomorrow.

Ok now, seems to be gone. Thanks to everyone who helped. Hope this info will help someone else in the future. I am not a fan of putting a computer in charge of my throttle like this. Anyone know of a mechanical conversion? Might be a good idea in the future.

It's a better idea to have the computer in control. Ford didn't do it to save money. This way, the computer can prevent a lot of potential problems. Plus, there's plenty of sensor failures that can have an identical efect on a mechanical throttle car.

Looks like your fault was more than likely either in the throttle body or the pedal position sensor, but I really can't give any advice on that over the internet, I'd have to do a good bit of electrical testing to determine the cause. Only thing I can suggest just as an easy check is to see if the throttle body is very dirty or anything.

But it seems like it is working fine now? Hopefully it was just some water incursion and won't happen again, if it does I reccomend taking it to a professional for diagnosis.

i had this same problem when i put in my gt500 throttle body..... whenever i would start it, it would roar up to about 2k rpm and then automatically die. over and over and over, and sometimes it would idle really weird and low and then die.

however, my problem was that the little spring that auto-closes the butterflies was not loaded, just sitting there....but you said you havent modded it at all, but it's really weird that it has the exact same symptoms.....

I worked on an equinox today that had 2 codes for APP/TP faults and 2 codes for transmission faults, and was stuck in a failsafe mode where it wouldn't accelerate. Turned out to be due to a clogged sunroof drain, that allowed water to run down the car's a-pillar into the kick panel, soaking a connector on the BCM harness. Dried it out, fixed the clogged drain, and problem solved. I found that interestingly similiar to your issue.

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